TDI EGR disabling

FR+TDI

Active Member
Jul 8, 2007
270
0
Carmarthenshire, Wales.
I've done a search but not found any specific info.

What is the situation with disabling the egr valve on our 150 PD ARL? It appears that the engine light will come on if its just disconnected? Not had a good look at it so asking for some info before I start removing things without need.

Cheers in advance.
 
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Muttley

Catch that diesel!
Mar 17, 2006
4,987
31
North Kent
Disabling the EGR stops the inlet manifold and EGR valve itself from choking up with cooked sludge, formed from (hot sooty exhaust gas) + (oily crankcase vent vapours).

This TDIclub page shows the crap that was cleaned out of one TDI manifold (about ¾ down).

EGR is solely there to reduce NOx. does this by reducing the peak combustion temperature, how hot it gets when the charge is burned in the cylinder. Under some circumstances the charge gets hot enough to burn the nitrogen in the air into nitrogen oxides, NOx. Exhaust gas is introduced as the only convenient *inert gas* to reduce the amount of oxygen in the charge which reduces the combustion temperature (and also results in inefficient combustion, increasing the other pollutant from diesel engines, soot)

VAG-com can be used to turn the EGR down to less than 10%, which is nearly as good as blanking it off.

The other part of the problem, crankcase ventilation fumes, can be taken care of by using a catch can.
 

FR+TDI

Active Member
Jul 8, 2007
270
0
Carmarthenshire, Wales.
Okay, so a VAG COM jobbie sounds like the easiest route to virtually reduce the operation of the EGR. Just need some one in South/West Wales with VAG COM now.... Anybody???
 

Seat Gooner

A.K.A Mark
Feb 28, 2009
1,952
0
Wisbech
Disabling the EGR stops the inlet manifold and EGR valve itself from choking up with cooked sludge, formed from (hot sooty exhaust gas) + (oily crankcase vent vapours).

This TDIclub page shows the crap that was cleaned out of one TDI manifold (about ¾ down).

EGR is solely there to reduce NOx. does this by reducing the peak combustion temperature, how hot it gets when the charge is burned in the cylinder. Under some circumstances the charge gets hot enough to burn the nitrogen in the air into nitrogen oxides, NOx. Exhaust gas is introduced as the only convenient *inert gas* to reduce the amount of oxygen in the charge which reduces the combustion temperature (and also results in inefficient combustion, increasing the other pollutant from diesel engines, soot)

VAG-com can be used to turn the EGR down to less than 10%, which is nearly as good as blanking it off.

The other part of the problem, crankcase ventilation fumes, can be taken care of by using a catch can.

Is that a good/bad thing then to calm it down ? if its good why is it there in the first place :confused:
 

brad1

Guest
another way to do it is, remove the pipe that goes to the top of the egr, and plug the pipe with a screw ;)
 

Muttley

Catch that diesel!
Mar 17, 2006
4,987
31
North Kent
Emission control legislation requires NOx emission to be controlled. Nox is a Bad Thing (TM) because it is implicated in smog formation. The evidence is not clear, and adressing NOx on its own is a poor answer.

The use of EGR to control NOx is nasty in any case, leading to increased soot formation and loss of engine efficiency.

NOx is not monitored by the ECU or tested at MOT. NOx measurement requires complicated and expensive sensors and testing.

Earlier ECU's, typically those on the TDI 90 and 110, don't set off the Engine Management light if you disconnect the electrics on the N18 valve or block the vacuum line.

Just to make my position clear, I've disabled the EGR on my TDI110 Toledo by disconnecting the electrical connector to the N18 valve.
 
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brad1

Guest
i have totally removed my egr on the 110, ive put a pd150 egr manifold on with a pd150 egr delete pipe, not EML light yet :)
 

Danny_FR

Soot? Meh...
Mar 1, 2007
373
0
Blackburn, Lancs
Turning the EGR down with VAG-COM doesn't work on 150TDI's (from '04 on IIRC). Tried it on mine and the next time I switched off the engine and restarted it, the value had returned to what it was before. The only way to disable it is to either block off the little vacuum pipe and put up with random CEL coming on and off, get a EGR deletion pipe (would still bring up the CEL) or get it mapped out.
 

FR+TDI

Active Member
Jul 8, 2007
270
0
Carmarthenshire, Wales.
Turning the EGR down with VAG-COM doesn't work on 150TDI's (from '04 on IIRC). Tried it on mine and the next time I switched off the engine and restarted it, the value had returned to what it was before. The only way to disable it is to either block off the little vacuum pipe and put up with random CEL coming on and off, get a EGR deletion pipe (would still bring up the CEL) or get it mapped out.

Cheers. Have you mapped yours out or blanked it off?
 

Danny_FR

Soot? Meh...
Mar 1, 2007
373
0
Blackburn, Lancs
Cheers. Have you mapped yours out or blanked it off?

I've just blocked mine off with a golf tee. Anything will do as long as it fits in the pipe and won't leak air through or gets sucked in to the pipe. The CEL light comes on and goes off as it pleases but I check it with VAG-COM regularly to make sure there isn't another reason why the light's come on.
 

ChrisGTL

'Awesome' LCR225
Nov 17, 2007
2,459
2
Huddersfield
Get one of these bad boys :)

DSCF1073.jpg


About £60 from Jabbasport, they will remap the EGR CEL light out too.